Skip a few "using namespace" that we don't really need.

third_party/WebKit/Source/core/html/HTMLSelectElement.cpp

Index: third_party/WebKit/Source/core/html/HTMLSelectElement.cpp
diff --git a/third_party/WebKit/Source/core/html/HTMLSelectElement.cpp b/third_party/WebKit/Source/core/html/HTMLSelectElement.cpp
index fe352c535ecfc9d2a09be45fb60f8816fffa66a6..3912b1b2d29a5406e93b53ddc53202bbacd87b11 100644
--- a/third_party/WebKit/Source/core/html/HTMLSelectElement.cpp
+++ b/third_party/WebKit/Source/core/html/HTMLSelectElement.cpp
@@ -74,8 +74,6 @@
 #include "platform/instrumentation/tracing/TraceEvent.h"
 #include "platform/text/PlatformLocale.h"
 
-using namespace WTF::Unicode;
-
 namespace blink {
 
 using namespace HTMLNames;
@@ -1678,7 +1676,7 @@ void HTMLSelectElement::defaultEventHandler(Event* event) {
     KeyboardEvent* keyboardEvent = toKeyboardEvent(event);
     if (!keyboardEvent->ctrlKey() && !keyboardEvent->altKey() &&
         !keyboardEvent->metaKey() &&
-        isPrintableChar(keyboardEvent->charCode())) {
+        WTF::Unicode::isPrintableChar(keyboardEvent->charCode())) {
       typeAheadFind(keyboardEvent);
       event->setDefaultHandled();
       return;